Pre-operative diagnosis of renal angiomyolipoma.

Preoperative diagnosis of renal angiomyolipoma was reviewed with emphasis on ultrasound and CT findings. Two cases were reported. Combined use of ultrasound and CT or conventional radiographs (with demonstration of fat radiolucency) are accurate preoperative diagnostic methods. Nephrectomy or unnecessary operation can be prevented. A small asymptomatic renal mass may be incidentally detected during ultrasound examination of the liver and gall-bladder. If CT or conventional radiographs confirm the presence of fatty tissue in the tumor, diagnosis of renal angiomyolipoma can be made. Then ultrasound follow-up is justified.